Pull start engine

silverbear

silverbear

The Boy Who Never Grew Up
In regard to the jack shift setups and difficulties in bump starting the engines...
It would seem to me that it might simplify starting if you had a pull start option on the motor. I don't have the jack shaft setup, but did recently buy an 80cc dual start motor for an additional bike. My other one is just the bump start. I find that I really like the pull start... I start it up and shut off the choke, let it run a bit to warm up and pedal away, letting out the clutch as I give it gas. None of this fumbling around as I go, trying to shut off the choke as I ride or on a cold morning leaving it open part way for a bit. The temptation is to look away from the road at the engine while fiddling, so for me at least it is a safer setup. It is also nice when you find yourself at the dip in a hill and have to pedal or walk the bike uphill to bump start it. So I like it. I did not like the hassles involved due to the wider engine and conflicts with the pedal crank. I had to raise my engine up above the arc of the pedal to get it installed on a 63 Schwinn American. But now that it is installed it is a sweet, hassle free ride.
Walter Silverbear
 
My bump start motor came from ThatsDax a couple of years ago and has given good service, many many fun miles. This new one came from BoyGoFast from ebay, around $140.00 with shipping. It seems more powerful than the old motor and is a good easy starter, a bit of choke when cold but only for a second or two, then smooth running. I had a good experience with both sellers.
Walter Silverbear
 
Pull start is definitely an option to pedal start with the Shift Kit. It also puts a lot less stress on the front freewheel. Some have had issues with the rope that comes with them breaking. They are easily replaced from what I hear. They usually break because the hole the rope comes out of in the housing is sharp and can cut the rope. That can be fixed as well.
 
Pull start is a nice option to have with a SBP shifter kit and high compression head. However, I try to only use the pull start as a backup incase my one-way bearing fails on my centrifugal clutch.
 
Are you saying donuts 31 that the kit with the centrifical clutch still jump starts? that would be great-

doesn't the rope pull make the difference between fitting between the cranks or not?
 
my 48cc engine from gasbike came with a dualstart and dual clutch. i have a centrifugal and a manual clutch and it can be pull or peddal started. but yeah its alot wider and first i mounted the engine high to clear peddals,then i switched my 8" crank peddals for 5" short crank peddals and lowered my engine,now my 5"short crank peddals clear my wide engine and my muffler.

one could also use wide 3-piece cranks and peddals but i didnt want to spend that kind of money when i found some short crank peddals from a exercise bike for $3.

the ropepull sticks out 1 1/2" one side and the cent clutch sticks out 1" on the other side,which makes the engine wider on both sides.
 
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Ah, I will be on the lookout for a giveaway exercise bike. Good tip! I wonder how much more work pedal assist will be on steep hills. Did you notice a difference?
Regarding the dual start. On my 80cc engine from boygofast you can either pull start or bump start and it is just a manual clutch.
Silverbear
 
i dont need to pedal assist at all even on hills,my motor has plenty of torque and power.
but even the short peddals are good for peddal assist or if you run out of gas or if you need to peddal start. i usually just use the peddals to make it look like im peddaling but usually im moving too fast for the peddals to actually do anything but spin freely.
 
I have a few long hills I ride which call into play some pedaling near the crest, nothing leading to cardiac arrest or anything so the shorter pedals should work fine. I think back to all the freebie exercise bikes I've seen and for cheap at garage sales... I suppose now that I'll be looking they'll be scarce. I do intend to get some exercise in removing the crank when I find one. Ha! I really like this pull start engine from boygofast and am thinking about ordering another one especially now that I know about the shorter pedal cranks. Great tip!
Silverbear
 
you may also be able to get some shorter cranks from a 20" bike or a bmx kids bike as long as it fits.

i went from cruiser standard 8" cranks to 5" cranks.
 
Good tip, Now that I have more options I'll be on the lookout next time I go to our local landfill. I think the other day I sa a 20" bike and didn't give it a second thought. Might still be there, too.
Silverbear
 
It dawned on me that I had put a different pedal crank on my electric motored 1934 Elgin Four Star... a nice short crank from a worksman folding bike... very nice quality and no rust. Last evening I traded with the one on my American Flyer with the china 2 stroke and it fits perfectly and looks great. So, no money involved and the bike is ready for the pull start assembly when it arrives, hopefully soon. The bigger crank is fine on the electric bike where crank size doesn't matter. Thanks for all the tips.
Silverbear
 
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